Device for use in the manufacture of artificial silk



Oct. 24, 1939. Q G, JANSEN 2,177,322

DEVICE FOR UsE IN THE MANUFACTURE OF ARTIFICIAL SILK Filed May 5, 1938 Patented o... 24, 1939 PATENT OFFICE,

DEVICE FOR USE IN THE MANUFACTURE OF ARTIFICIAL SILK Comelis Gerrit Jansen, Arnhem,

signer to American Enka Netherlands, as- Corporation, Enka,

N. 0., a corporation of Delaware Application May 5, 1938, Serial No. 206,246

In Germany June 28, 1937 1 Claim. The present invention relates to the manufacture of artificial silk thread and the like and more particularly to an'improved spinning'funnel for use in the centrifugal bucket spinning process.

In the collection of threads of cellulosic origin accordingto the bucket spinning method, use is made of a reciprocating thread guide funnel positioned above the axis pf rotation of a bucket or pot. The thread is laid up in the form of a cake by means of the centrifugal force created by'the rotation of the bucket and the movement of the thread guide funnel. The thread emerging from the outlet at the lower end of the funnel contacts with and rides around the mouth of the funnel and thereby creates considerable friction which is detrimental to the freshlyspun, extremely sensitive, gelatinous thread. In addition, over a period of time such friction causes a wearing awav of the wall of the spinning funnel adjacent its mouth and this accordingly lessens the life thereof.

United States Patent No. 2,097,034, issued to Gerhard Jan Meerdink, relates to the manufacture of wool-like artificial threads by the employment of a spinning funnel provided with a roughened lower portion adjacent its mouth." The toughening of the lower portion of the Meerdink structure is elected by applications of an abrasive material at this location. Said patent discloses various ways of roughening the thread guide funnel so that a thread emerging therefrom will be subjected to-a nicking action vhereby to impart to the thread in its-final form the appearance of wool.

In contradistinction to the aioreclescribed patout which provides an abrasive thread contacting surface to produce a special type of thread, the present invention is concerned with a specific problem in the manufacture of normal thread.

It is an object of the present invention to treat the lowermost thread contacting portion of a thread guide. funnel in a manner such that a greatly reduced friction will be had between the wet thread and the funnel as the thread emerges therefrom during theformation of a cake.

This invention additionally contemplates the provision of an improved spinning funnel for use inthe manufacture of normal artificial threads having a mechanically or chemically treated surface at its outlet which will effect reduced friction between the thread and funnel during a normal operation.

In the accompanying-drawing, theilgure represents a normal thread suide funnel designated by the numeral I having a corrugated mouth 2.

an etched surface adjacent its mouth causes suc- The lower portion of the funnel is in section to show the treated portion 3 thereof. The funnel in general consists of glass or its equivalent and the rim defining the mouth thereof is corrugated or undulatedin accordance with the improve- 6 meat described and claimed in United States Patent No. 2,100,595, issued to Comelis G. Jansen.

The lower portion of the present funnel has been treated chemically as by applying hydrofluoricf acid to its surface. The application of th ydro- 10 fiuoric acid, for example, can be efl'ec ed by means of a rubber sponge soaked in the acid and pressed against the surface. If it be desired, this etching can also be undertaken by means'of a sandblasting operation. In any of these conditioning steps the etching provides a minutely uneven surface, whereby the projections and depressions are smaller than the contact surface of the thread.

A spinning funnel treated in the foregoing manner has marked utility and can be used to advantage over the normal type of funnel.- It is well known that' the centrifugal force created within the bucket during the formation of a cake decreases as'the active diameter of the cake becomes less. Now, by reducing the friction between the mouth of the spinning funnel and the thread emerging therefrom in accordance with this invention, tension variations are substantially eliminated and the appearance and quality of the thread is improved. Utilization of a spinning funnel made in accordance with this invention causes a finished thread otherwise produced by a normal process to have improved dyeing properties without the employment of expensive corrective steps. Another distinct advantage which results from the use of a spinning funnel made in accordance with this invention is that the spinning of larger cakes, or cakes having agreater thickness is permitted without the necessity of increasing the driving speed of the bucket. Conversely, a normal size cake can be produced by using a lower'R. P. M. and also a lighter weight thread can be spun and collected. These advantages over the past practice are made possible because the friction caused in past practice counteracted or overcame the centrifugal force of the bucket during the latter stages of collecting the cake and the thread could no nger be properly laid up against the inner wall hereof.

While the theory upon which the present invention is based is not fully understood, it is thought that the utilization of a funnel having ceeding portions of the wet thread passing therewithin the minute etched depressions. In the utilization of a funnel having a smooth surface adjacent its mouth with which the thread contacts, a continuous liquid film exists between the thread and funnel surface which, due to interfacial forces or cohesion, tends to objectionably impede the passage of "the thread from the funnel mouth. 1

j vention has been described, various methods'and apparatus can be employed for etching the lower- Whereas the preferred embodiment of the inmost surface of the spinning funnel to thereby over to *glide upon globules of liquid dispersed decrease the friction normally caused by a thread I emerging from the-mouth thereof.

What is claimed is:

In an apparatus for the manufacture of rayon and the like, a spinning funnel having a hard thread guiding surface etched adjacent its outlet end to provides. myriad ofminute depressed portions capable ofeffecting the entrapment of globules of liquid thereby to form an antifriction s face for the thread during the operation of m the apparatus commms GERR'IT YJANSEN. 

